A sliding bearing is known in the art including a bearing alloy layer having a number of circumferentially extending annular grooves, which are axially spaced apart, formed in its inner peripheral surface, with a circumferentially extending peak defined between a pair of axially adjacent annular grooves, an intermediate layer which coats the surface of the bearing alloy layer, and an overlay layer which coats the surface of the intermediate layer, the arrangement being such that when the overlay layer and the intermediate layer are partly abraded beginning from the surface of the overlay layer, the overlay layer and the intermediate layer which remain within recesses of the annular grooves as well as the peaks of the bearing alloy layer become exposed (See Japanese Laid-Open Patent Application No. 205,014/1985).
With a sliding bearing thus constructed, when the overlay layer and the intermediate layer are partly abraded beginning from the surface of the overlay layer, the overlay layer and the intermediate layer which remain within the recesses of the annular grooves as well as the peaks of the bearing alloy layer become exposed, thus preventing the intermediate layer from being extensively and immediately exposed as occurring in a sliding bearing of the same kind, but which is not provided with annular grooves. In this manner, a drastic reduction in the seizure resistance which may be caused by an extensive exposure of the intermediate layer can be effectively prevented.
However, according to the cited Application, it is described that the depth of the annular groove or the height of the peak be equal to or greater than one and one-half times the thickness of the intermediate layer and be equal to or greater than 5 .mu.m in order to achieve the intended effect.